I have 280 miles on myVS speedster with 2010cc motor with A-1 exhaust and she has just started to backfire--even after she is warmed up??
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Backfire can come from a few things.
1. Timing
2. Intake Leak
3. Exhaust Leak
4. Carb Adjustment
Jerry - where do you live? Possibly within a visit distance from
vintage speedsters? Sounds like something Kirk could have fixed in a few minutes And he's usually great at post delivery fixes.
3000 miles-----NJ---car ran great first 260 miles(except for brake problem) so I don't think its timing or carb---but the exhaust was worked on-ill ck there--thanks
I had the same thing--I replaced the exhause gaskets---where the exhaust comes out of the engine. Now I know I might have fixed it with just tightening those nuts.
See if your exhause nuts are loose--don't go crazy with tightening too much---see torque specs in Clymers.
Good luck with it!
Look for black carbon at exhaust ports or sleeve joints, check plugs to see if running rich or lean.
As mentioned, timing, intake and exhaust leaks, carb adjustment and,,, clogged idle jets if you have dual carb's. Go here is you choose to clean the idle jets then click on the photo of the carb's. http://www.spyderclub.com/view...1&p=68626#p68626
I found some loose header bolts but that did not fix the problem--the motor sounds like its gonna blow--cant even drive it now--kirks mechanic roland had me adjust the carbs but it did not help -im at 300 miles could valve adjustment be the cause---might have to take it to a vw dealer at $115/hr
VW dealer? I doubt that you will find one that works on A/C VW engines. You need to find a specialist, probably an old timer. The one I used for our '63 bug was a former formula V hobbyist. And, BTW, his rate was nowhere near $115 per hour.
Unless the dealership has some older fart still working there (not likely these days, as they don't pay that well) none of the younger guys will know what to do with an older aircooled motor. You could call and ask, but...Have you ever noticed any shops around that have aircooled VW's parked in front? Even a dune buggy or tube framed rail will tell you someone there plays with these things. Do you know of any local VW clubs? If no one here knows of a shop locally for you, go on the Samba (VW site) to the "Performance- Engines/Transmissions" forum and ask if anyone can recommend a local mechanic. And yes, it's time for a valve adjustment, but unless a bunch are really far out I can't see that causing your problem. Does it sound really loud, like it's completely unmuffled (think top fueler)? Or clattery, like there's something wrong inside?
First. Relax. It's probably something minor. 2nd. I agree. Find a local air-cooled VW mechanic. You're wasting your time at a VW dealership. Google up your local Vintage VW Club. I'm sure you will find help there right away. Here, this might get you close http://www.cjvws.com
I had several 911's and a 930 turbo--I was using a great Porsche mechanic-gene at autohaus-think ill have it towed to him Monday-canceled my apt at vw dealer-thanks for the help-cars not even driveable now-way to much backfires out the exhaust and now I here an air sucking pulsating sound from the right empi area
Hopefully not a stuck valve,maybe sticky rocker arm,maybe adjustment ,and nobody switched plug wires on you. if it was running well before and carbs are clean.....????!
plug wires are good----and yes its loud like gun shots-not much room to see or pull jets from the sides--side firewall to close for even small flathead---seems like the motor has to come out to really have good access-hope that's not the case